World electricity consumption is expected to grow 60% from 2011 to 2030, being most of this new generation capacity attributed to intermittent renewable energy sources such as solar or wind. In this scenario there are two main challenges for the future: energy efficiency and energy storage. Researchers from UPM have developed thermophotovoltaic devices for the direct conversion of high temperature heat into electricity. Using these devices, SILSTORE develops turnkey solutions for waste heat recovery in high temperature industries (e.g. steel factories). Besides, SILSTORE is developing a patent-pending technology for ultra-high temperature energy storage able to provide extremely high energy densities, much higher than current existing technologies (e.g. batteries) at affordable prices.
A thermophotovoltaic (TPV) device operates in the same way than a solar cell to transform the radiant heat emitted by incandescent bodies into electricity. The attractiveness of TPV if compared with conventional heat engines is that it does not require moving parts nor direct contact with the heat source, making it a simple and robust alternative to conventional heat engines for extremely high temperature operation. Furthermore, TPV is able to produce extremely high power densities, in the order of 100-500 times than that of a conventional solar cell. SILSTORE is using these devices for the waste heat recovery in high temperature industries, such as steel and glass factories. SILSTORE has also patented a technology for high temperature energy storage that uses TPV devices for energy conversion and molten silicon (at 1400C) as storage medium. This system has potential to reach higher energy densities than competing technologies (e.g. batteries) and uses abundant materials, such as silicon, the second most abundant element on earth crust.
“SILSTORE uses silicon as storage medium. Silicon is the second most abundant element on earth crust and allows reaching energy densities as high as 500 kWh/m3, well above the potential of most of the competing technologies”
“In a steel factory, for instance, there exist large incandescent surfaces radiating heat 24 h the 365 days of a year. SILSTORE provides photovoltaic solutions to recover this heat and produce electricity on-site”
“Thermophotovoltaic converters generate electricity from incandescent heat and produces extremely high power densities, in the order of 100 to 500 times than that of conventional solar cells”
Instituto de Energía Solar (IES-UPM)
Innovation, Commercialization and Entrepreneurship Area
Centre of Support for Technological Innovation – UPM